A ventilating system for a commercial kitchen typically includes a hood located over the cooking equipment and passage structure from the hood that leads to an exhaust duct that discharges to the outside atmosphere, and a blower or fan draws the kitchen fumes through the exhaust duct for discharge to the outside atmosphere. The system removes heat, grease, and odors from the kitchen and greatly improves the comfort factor of the employees as well as the patrons.
The ventilating system further typically has a damper which can close the flow passage between the kitchen and the exhaust duct, and this is used during a kitchen fire to prevent the flame from being carried up the exhaust duct. This helps smother the fire and further minimizes the possibility of having a fire in the exhaust duct. However, a kitchen fire proximate the hood structure can heat and warp the damper, so that service of it sometimes is necessary; but more frequently, service of water spray equipment located inside the duct work is required even on a routine basis and access to such equipment is thus required.
Several patents which relate to the general type hood construction to which this application pertains and over which the invention forms an improvement are the Gaylord U.S. Pat. No. 2,813,477 entitled Safety Ventilator Unit; the Graswich et al. U.S. Pat. No. 2,961,941 entitled Grease Extracting Attachment for Ventilators for Kitchen Ranges; the Gaylord U.S. Pat. No. 3,055,285 entitled Kitchen Ventilating System; the Gaylord U.S. Pat. No. 3,207,058 entitled Kitchen Ventilating System; the Gaylord U.S. Pat. No. 3,247,776 entitled Kitchen Ventilating System; the Gaylord U.S. Pat. No. 3,611,908 entitled Fail-Safe Damper Control for Kitchen Ventilator; and the Gaylord U.S. Pat. No. 3,785,124 entitled Pollution-Free Kitchen Ventilator.